Shipud writes: Raytheon has secretly developed software capable of tracking people's movements and predicting future behaviour by mining data from social networking websites according to this story from The Guardian.

An "extreme-scale analytics" system created by Raytheon, the world's fifth largest defence contractor, can gather vast amounts of information about people from websites including Facebook, Twitter and Foursquare.

Raytheon says it has not sold the software – named Riot, or Rapid Information Overlay Technology – to any clients. But the company has acknowledged the technology was shared with US government and industry as part of a joint research and development effort, in 2010, to help build a national security system capable of analysing "trillions of entities" from cyberspace.

The power of Riot to harness popular websites for surveillance offers a rare insight into controversial techniques that have attracted interest from intelligence and national security agencies, at the same time prompting civil liberties and online privacy concerns.